Mining-machine



" Fig. 1.

UNITED STATES PATENT O FICE. a

;; cHARLEs W. coLvIN, or wILKEsBAERE, PENNSYLVANIA.

MINING-MACHINE.

SPECIFICATION forming. part Of Letters Patent -NO. 282,274, dated July 31, 1883. Application filed February 1, 1883 (hl'o model.)

To allwhom it may concern..-

Be it known that. 1, CHARLES W. CoLvIN, a citizen of the United States, and a resident of 'Wilkes-Barre, Luzerne county, Pennsylvania,

5 have invented certain Improvements inMining-Machines, of which the following is a specification.

The main feature of my invention relates to certain improvements in the coal-drilling machine for which Letters Patent of the United States N 0.223, 590, dated January 13, 1880, I were granted to J. R. Howells; and the object of my invention is to so construct the drill that the bit will be fed forward automatically only in proportion to the degree of hardness of the coal being out. Afurther object of my invention is to so construct the. feed-wheel that it will adapt itself to irregularities in the twist of the drill itself. These objects I attain as more fully described hereinafter.

In the accompanying drawings, Figure 1'. is avertical section of adrill embodying my in- .vention; Fig. 2, a plan view, partly in. section; and Fig. 3, a detached sectional perspecform of screw-nut I propose to use. Referring toFig. 1, A represents a suitable frame or standard for supporting the drill, similar to the stock illustratedin the abovecited Letters Patent. I llhe standard is provided with toothed jaws, one of which is a continuation of the standard, and the other, B, hinged thereto. The standard and the arm b of the movable jaw B are provided with a bolt, b, and nut bi, whereby the jaws may be expanded after insertion into a suitable opening in the breastofcoal to be drilled, so as to firmly hold thestandard and its parts in position.

On the standard A is mounted a frame, M, having bearingsor collars E E, through which freely passes the drill G, the latter being pref- I erably made in two parts joined by a socket,

g, with their twists The bevel or feed wheel F, through which the drill passes, and which gears into the the collar, as shown in Fig. 3, for the recep tive view of a modification, and illustrating a reversed, as shown in threads adapted to the twist ,of the drill. This feed wheel F is in frictional contact with the 5o bearing or collar E, so that when the crankhandle H is applied to the end of the shaft N, as shown in Fig. 2, a rotation of the handle to the'right will cause the wheel F to rotate, and its threads acting on the twist of the drill will advance the latter in the direction of the are row. When an increased resistance is offered to the advance: of the drill, the latter will simply rotate with and at the. same speed as the wheel 5 but as the' threads in the hub of the wheel continually tend to push the drill forward the latter will advance just as rapidly as the material being cut will allow.

Instead of having the hub of the wheel F bear simply against the face of the collar E, an annular recess may be formed in the end of tion of the hub of the wheel F, to increase the frictional surface between the two, only sufiicient of the hub F being indicated in this figure to illustrate the modification.

As the twists of the drills G are not always uniform, I prefer to swivel or pivot the threads f f in the feed-wheel F, as shown in Fig. 3, so that these threads will always adapt themselves to the twist of the drill.

I claim as my invention- 1. The combination of the frame of a mining-drill having bearings or collars for the free passage of the twist-drill with a driving-shaft and bevel-pinion, and a loose bevel-wheel gearing into the said pinion and having threads adapted to 'the twist of the drill, substantially as set forth.

2. The combination of a rotary drill with a feed-wheel having swiveled threads, as and for the purpose described. y

In testimony whereof Ihave signed my name to this specification in the presence of two subscribing witnesses.

. G. W. GOLVIN. Witnesses:

THOMAS DUGAN, HUBERT HowsoN. 

